Project Blue Book Case File
Thule AFB, Greenland, April 1952April 1952
Summary
On April 25, 1952, at Thule Air Base, Greenland, an Air Force lieutenant and a civilian Arctic rescue expert reported a vapor trail. The sighting happened about 0100 hours (1:00 a.m.), when the station had daylight. The sky was clear with unlimited visibility.
The witnesses said they saw a vapor trail forming about 80,000 feet above the station. A weather observer stated that an aircraft would have to be above 12,000 feet to create a vapor trail. Only the trail was seen. No lights like those used on aircraft were observed. One witness watched the trail form, but his binoculars could not reveal any object at the starting point because of the high altitude.
One known aircraft, Charlie 54, was approaching the station for landing at about the same time, but its pilot said he was flying too low at 4,000 feet to create a vapor trail. Officials noted a similar incident was alleged in January 1952 but had not been reported. On the Air Force record card, the case was marked Probably Aircraft.
Reported location
Thule AFB, Greenland, April 1952
Date of incident
April 1952
State / country
? / XX
Page count
2 scanned pages
USAF evaluation
unknown
Microfilm
T1206, Roll 9